Brother Knows Best
by Gaming Fractal
Summary: Or rather Nijimura didn't want to know. Nijimura returns to Japan for college, finds out his underclassmen are all dating, and his brotherly instincts start tingling. Unfortunately for him, he meets the in-laws in the worst possible ways. Brotherly!Nijimura Genderswap!GOM.


**Brother Knows Best**

 **Summary:** Or rather Nijimura didn't want to know. Nijimura returns to Japan for college, finds out his underclassmen are all dating, and his brotherly instincts start tingling. Unfortunately for him, he meets the in-laws in the worst possible ways. Brotherly!Nijimura Genderswap!GOM.

 **Disclaimer:** I do not own KnB

* * *

At age eighteen, Nijimura Shuuzo returns to his homeland of Japan. As his father has already recovered, he decides to continue his education in Japan. He rents out a small studio for himself as the rest of his family opted to stay in L.A. He makes new friends in his new high school, and when he had the time, tried to reconnect with old ones. Among those he contacted were his batch mates from Teiko, and his troublesome underclassmen, aka the generation of miracles.

Well, he was able to get in contact with Akashi Seira, and with her help, they were able to plan a small reunion. This was the reason why he was currently heading to a cozy looking café near his university one Sunday afternoon. However, once he entered the café, he was immediately met with two blurs of pink and yellow respectively that latched on his arms. "Nijimura-san!" They cried out, and a small smile appeared on Nijimura's face. Looks like some things never change.

"Kise, Momoi. Great to see you two looking well." He greeted. Soon he was pulled over to a rather large booth where the others were waiting. As soon as the others saw him they began greeting him, which he returned before sitting down. They then placed their orders, and Nijimura was pleased to know that the place served good coffee. The hours went by as they talked, about their lives, basketball, and even random things. For the most part, he listened to them.

When he did speak though, he saw that they were quite attentive to what he was saying. But he inwardly noted that they haven't changed much. No, he was aware that they had physically matured, but he wasn't talking about that. As he listened to Kise retell a story of a certain summer camp, much to Midorima's displeasure, his memories of middle school seemed to overlap into the faces he currently stared at. He inwardly wondered when he had become such an old man.

He commented every now and then, and praised them for their achievements. He could see them preening a bit when he did and he inwardly chuckled at how that part of them hadn't changed as well. He felt a small smile appear on his face as they spoke. His troublesome underclassmen had for the most part, grown up to be respectable young individuals, while still being complete terrors in basketball. In all honesty, he saw them like younger siblings, so he was glad that they turned out all right.

While they were planning a meet up for a game of street basketball on a later date, a metaphorical bomb was dropped on Nijimura, courtesy of one Kuroko Tetsuna. "Uhm… Would it be alright if we invited our respective boyfriends as well?" She had asked innocently enough. But Nijimura almost dropped his cup from her words. 'Boyfriend' The word reverberated in his head almost hauntingly. He resisted the urge to bang his head on the table.

Of course, his underclassmen were not only talented but had become beautiful young women and a handsome young man. The girls could be called beauties, each possessing their own charm. While Momoi was what people would call a pretty boy.

Of course, they would get their fair share of attention from the opposite sex. He then remembers Teiko, where he did a lot of head whacking to keep hormonal brats from staring too much, among other things. He remembers how things escalated when his underclassmen were in their second year and he literally had to beat some overaggressive brats away with a stick(it was actually a pipe, but details).

It was natural for them to want to date at their age.

Of course.

But that didn't make it easier for him. Not at all. To him, they might as well still be first years in Teiko. It also didn't help that he felt protective towards them. Had his younger sister been here, she would have teased him that his big brother senses were tingling.

"I want to meet them." He finally says. In hindsight, this had been the start of many headaches.

* * *

 **Daiki & Momoi**

When Tetsuna first brought up that her former captain was going to be visiting Seirin, the first thing Kagami asked was. "Is he strong?" Which caused sighs all around. "I cannot gauge his current level as I have not faced him recently, but during middle school he was definitely one of the strongest players." Tetsuna answered and a feral grin appeared on Kagami's face. "Then I have to challenge him." He said, a determined glint in his eyes.

"But why would he visit us?" Aida Riko asked. "…I think it due to personal interest." Tetsuna answered. "Personal interest?" Koganei asked and Tetsuna nodded. "As he is like an older brother to the generation of miracles, it is accurate to say that he wants to meet his new in-laws…" She replied evenly. It took almost a minute for them to understand the implications of such a statement, but once it sunk in, both Kagami and Riko started panicking.

"You should have told us that from the start Kuroko!" Riko shouted before rushing to make preparations for his visit. Kagami on the other hand looked utterly lost, as he thought about what to do. He knew that he wanted to make a good impression on the man, but how? In the end he decided to hit the showers. At the very least, he should be presentable while in front of the former Teiko captain. That should count as something, right? So he ran to the shower room.

Hyuuga sighed. With Kagami and Riko's state being like this, they probably wouldn't get much practice in so he ended practice all together before heading for the lockers to shower as well with Izuki patting him on the back. "Now now, it's just a one time thing anyway Hyuuga." Said captain sighed. "It damn better be." After a few minutes Kuroko emerged from the girl's locker room. She only needed to change back to her uniform since she hadn't really gotten to practicing, as she arrived late due to cleaning duties.

"Kuroko!" She heard someone call for her and turned to see Koga running up to her. "Sempai?" She called asked Koga reached her panting. "Y-You'll never believe this!" He said before continuing. "The pets appreciation society is in a total chaos. They brought their pets over, but something spooked them and their pets ended up running away."Her mouth opens into a small o at the news. "That's horrible." She said a bit more infliction in her tone than her usual deadpan, and Koga nodded.

"But that's not even the worst par-" Whatever else he was trying to say was drowned when an ungodly scream erupted from the boys locker room. Moments later, three dogs came running out. None of them being the Alaskan Malmute that was Seirin's team mascot, Nigou.

* * *

Nijimura Shuuzo looked at the school. "So this school was built only a few years ago. No wonder everything's spick and span." He commented as he looked at the Too pair beside him. "By the way, is it really alright for us to just enter Seirin like this." He asked. "Sure Satsuki and I do it all the time." Daiya answered, which worried Nijimura slightly. After all, should students from other schools be able to enter so easily, and for that matter why was the Toou pair spending so much time in this school instead of their own school?

But he kept those comments to himself. No need to give himself a headache so early in the visit. They eventually saw the gym and Nijimura had to nod in appreciation. It was one of the better looking sports facilities around. But when they got closer to the structure, they started to hear screaming? "Over there!" A voice called out. "Koga! Get it." Another shouted before the sounds of people running could be heard.

"What on earth is going on in there?" Satsuki said as he turned to his companions. "No clue." Daiya answered with a shrug before barring her teeth. "But it sounds like fun." She added, and before either male could advise her or stop her, she opened the door. All three of them froze at the sight in front of them because there Seirin's basketball club was running around trying to catch three dogs of various sizes, some half naked.

"Ah, Nijimura-san, Momoi-san, Aomine-san, you've arrived." A voice suddenly says, causing the trio to jump slightly. Daiya is the first to speak."Tetsu! Haven't I told you not to do that! And since when have you been there?" She half-shouts. "I've been here all this time." She answers simply. Nijimura holds back the comment that her misdirection is as strong as ever, and instead asks Kuroko, who is fortunately clothed, about what is going on.

Tetsuna opens her mouth to answer when a honk like sound beats her to it, and from the slightly open side entrance of the gym slips inside a duck, of all things quickly scampering away inside the gym. "Come back here!" A voice rumbles, sounding much like that of an ogre's; before the side entrance is opened completely. A high school girl with very apparent bloodlust appears on the other side holding a kitchen knife in hand.

Her eyes zero in on the duck and she clutches the knife even tighter. "I'm going to turn you into Peking Duck!" She roared as she began to chase the bird down. At the sight of their coach on a warpath, most members forgo their chase for the dogs in favor of trying to stop her instead. "Rikorin?" Momoi calls out, and Nijimura could feel uneasiness and dread settle into the pit of his stomach. He knows that nickname.

Momoi wouldn't stop talking about her on their way here. Rikorin was apparently the name of Seirin's coach and Momoi's girlfriend. But as he saw the woman who was mercilessly trying to hunt down a duck despite the basketball club trying to talk her out of it, he couldn't match her to Momoi's claims that his girlfriend was both cute and wonderful. The adjectives frightening and murderous, probably suited the girl more.

From the corner of his eyes, it looked like none of his companions knew what to make of this scene either. But when the girl, Rikorin, Riko? managed to corner the duck, that is when Momoi moves running towards her in full speed. "Rikorin No!" He screams.

* * *

Loud noises caused Taiga to stir. Blearily, he opened his eyes only to find himself slumped down against the wall of the locker room. As he tried to piece things together as to why he was there, he hears an ear piercing scream. "Rikorin no!" His body immediately reacts and he gets up before running outside. "What happened?!" He roared, and immediately all eyes are on him, and all who see him stop in their track including Momoi and Riko.

There is silence and then. "Kagami! What are you doing going around in nothing but a towel!" Daiha screams at her boyfriend, face completely red. But as if fate was conspiring against him, the towel's flimsy hold on Kagami's waist ended then and there, and it falls to the ground.

* * *

On that day there were several misunderstandings. Kagami had just finished showering while the others had just began to changing out of their practice clothes, when the dogs entered through the broken ventilator that is positioned near the ground. At the sight of three dogs popping into the locker room, Kagami lets out a scream before passing out due to his dog phobia. While the others wanted to do something about their unconscious ace, they decided to do something about the dogs first.

Some forgoing clothing and others forgetting the fact that they were only half dressed before rushing out to catch the dogs. Somewhere along the chase, Izuki had the gall to make a pun about who let the dogs out, and was promptly whacked upside by an irate Hyuuga. While on the other hand, Riko, had rushed to the home Economics room to prepare snacks for their guests. Thankfully, she already had a cake prepared in advance.

To be honest, she had prepared it as a surprise for the boys and girl of her team, but it would have to do. She neither had the time to go to a bakery, nor the time or ingredients to make something else. She reasoned that she could just make another one for her boys and girl on a later date. After taking it out of the fridge, she left the cake on the counter to get a knife to cut it so she didn't have to later. But she heard a crash and turned just in time to see that a duck had knock the cake down, plate and all.

As it turned out placing the cake on the tabletop by the open window of the Home Ec. Room that was located on the first floor had been a bad idea. Said duck was apparently one of the runaway pets. But Riko had been so enraged by the duck that ruined her special Zinc cake that she had chased it all the way to the gym, completely forgetting her surroundings. She did all that while holding a kitchen knife in hand.

* * *

That day, Seirin learned to thank small mercies. The first being that no one ended up being food poisoned thanks to the duck(members would later give it bread crumbs in thanks). The second was that while Kagami was absolutely horrified, at the very least he had boxers underneath his towel, even if they were his burger print ones.

* * *

 **Midorima**

Takao stole a glance at his girlfriend, Midorima Shinka who was currently seated beside him a look of slight unease on her face. "Now, now, relax Shin-chan." He says to her before adding. "I mean, we'll meet your former captain, he'll give us his blessing, and we'll all be on our merry way." He said before his eyes widened dramatically. "Or are you thinking he'll disapprove of me?" He said mock hurt in his tone as he placed his hand on his heart.

From beside him, Shinka sighed. "That's not it." She finally says after a while. "A penny for your thoughts then, Shin-chan?" He says and he watches as she tucks a stray lock of green hair behind her ear. "… Cancer's ranking today is seventh." She reveals and he perks up at that. "That's not bad!" He tells her. "It's not particularly bad, true. But it's not particularly good either. Oha-Asa warns Cancers to be careful today, especially when interacting with others."

"By the way, what's Scorpios' rank today?" He asks curiously, and for the second time that day, Midorima sighed. "Last place. You're supposed to be cautious towards accidents today." She tells him before massaging her temples slightly. "To be honest, I would have preferred to introduce you to Nijimura-san on a more auspicious day, but what can we do? The die has been cast." She tells him before going over to the rickshaw and taking a lacross stick out.

She tosses it to him and he catches it easily. "That's your lucky item for today. Make sure to keep it to you as close to you at all times." She says seriously, and Takao cooes. "Shin-chan! Your caring side is so cute!" Shinka immediately bristles at the words. "Shut up fool." She tells him, looking away but Takao can see the faint blush on her cheeks anyways. Takao laughs. "Shin-chan's a tsundere through and through." He says before placing the lacross stick under the bench.

"You're supposed to hold onto it, Takao, for maximum effect." She chides and Takao merely waves her off. "Don't worry Shin-chan, it's close enough." He tells her before adding. "Besides, if I held onto it, then how can you sit on this bench with me comfortably?" Shinka said nothing, because she knew he had a point as the lacross stick was rather large. "By the way, what's your lucky item for today anyways, Shin-chan?"

Instead of answering Shinka grabbed her knapsack from the rickshaw before opening it and bringing out a riding crop. Takao's mouth drops slightly at the sight of it. "Where on earth did you get that, anyways?!" He asks, incredulous. "I borrowed it from Akashi. One of her hobbies aside from Shogi and basketball is horse riding." She answers as she returns to the bench. Takao says nothing but merely hums slightly, before a thought occurred to him.

"Then how did you get it so quickly if you borrowed it from Akashi? I mean isn't she in Kyoto?" The look she levels him with might as well tell him _Are you kidding me?_ "She is in Kyoto, yes. But the Akashi main house, as well as her equestrian equipment is in Tokyo. When I called her about the riding crop, she had one of her maids send it to me at once." She answers before sitting back down on the bench, being mindful of the lacrosse stick.

"That makes sense..." He said as he eyed the riding crop. "Hey Shin-chan? Can I borrow it for a sec? I've never seen one in real life before." He requested and Shinka looked at the riding crop before looking back at Takao. "Be careful with it then." Shinka grumbled before handing it to the black haired male. "That was apparently given to Akashi by her father as a congratulatory gift when she won her first equestrian competition."

"No problem!" He answered, examining it. A few moments later he stood up, and walked a few feet away to prevent any untoward accidents, before giving a few experimental flicks of the riding crop. "Hmm… So this is what it feels like." Takao mumbled, a small smile on his lips, satisfied now that he knew. He then made for the bench. "Here you go Shin-cha-?!" He wasn't able to finish as he tripped over the lacrosse stick.

One of hand managed to catch himself on the bench's backrest, and one of his knee was on the bench seat. But he was also currently half-lying down on Shinka, and they were so close that their chests were almost touching. The sound of something being strangled caught their attention, and they turned to see an older teen with black hair, looking at them with a pale face. Noticing how Shinka's own face was quickly paling, he came to the conclusion that the other teen was probably her former captain.

Thinking back on it now, being caught in a compromising position with your girlfriend, while you were out in a public park during the afternoon, holding a riding crop on your other hand wasn't the best way to make a good impression. Nijimura had immediately turned around and said that he'd pretend he didn't see anything before quickly leaving. A few seconds later Shinka had shoved Takao off, her face completely red with both anger and embarrassment and screamed. "Die fool!"

Takao should probably start to heed Shinka's warnings more from now on.

* * *

 **Kise**

When Kise Ryoko first brought up the idea of him meeting her former Teiko captain, he hadn't been thrilled about it. But since it looked like it was important to her, he agreed. "Thanks a lot sempai! I'm sure Nijimura-san will totally approve of you!" She had gushed out. "You think?" He asked an eyebrow raised. "Of course sempai! What's there not to like about you?" She immediately replied, and he could feel his cheeks warm slightly at her unabashed declaration.

"Saying things like that with a straight face…" He grumbled. "You're such a brat." Ryoko laughed at that. "But I'm your brat, aren't I?" She said before taking hold off his arm. Kasamatsu's face reddened even more. "…Yeah, you are." He said after a few seconds before ruffling her hair. After that there was a comfortable silence as they resumed their walk. "By the way, Kise…" He began, and the blonde looked up. "Hmmm?"

"How's the team doing? You aren't slacking off now are you?" He asked and when Kise visibly gulped, his suspicion rose. "Ah, well about that Sempai, I haven't been to practice much…" She started, and Kasamatsu's brows started furrowing. "The thing is I have remedial lessons." She admitted. "It's cause my modeling jobs have been piling up and I didn't have the time to study for my tests…" She hurriedly explained, though she could see her boyfriend's temper rising. "Kise..."

Though they were dating, and he had graduated from Kaijo, that didn't mean he graduated from his job as a guiding sempai. Not to mention how old habits die hard, which is why the next thing he knew, he was already whacking Kise. "Sempai!" Kise whined. "Kise what have I told about balanci-" He never got to finish when he heard someone else call the blonde model out. They turned only to see the person Kasamatsu could recognize as Nijimura due to a picture the blonde showed him before.

Nijumura's face looked angry. At first he didn't get it, until it clicked. He probably saw him whacking Kise, and got the wrong idea. But before he could speak to clear up the misunderstanding, Kise spoke up. "Wait Nijimura-san, it's not what you think!" She begun, and Kasamatsu relaxed, it looked like his brat had this. He saw as Nijimura's face relaxed slightly at her words. Kise then gestured to Kasamatsu. "This person is Kasamatsu Yukio, he's my former captain from Kaijo and my boyfriend."

"What he did a while ago, he wasn't doing it to hurt me at all! It was just tough love!" She told him. "…Is that so?" Nijimura asked, sounding and looking a bit unsure. Kise nodded in earnest. "…Sempai hits me all the time, so that level of whacking is nothing!" She proudly declared much to the horror of both males. "If he really wanted to hurt me, he'd use his drop kick on me!" Kasamatsu resisted the urge to face palm. "Kise, please just shut up."

Kasamatsu later makes a mental note to never let Kise explain again.

* * *

 **Murasakibara**

After making plans to meet Murasakibara Atsuko's boyfriend, Nijimura found himself waiting for them to arrive from the train station. But the moment he sees the male that is walking next to the violet haired underclassman he has to do a double take. But no matter how many times he rubs his eyes, the sight in from of him doesn't change, no matter how much he wishes it would. The couple stops only when they're right in front of him.

"Hey, Shuuzo!" The male greets pleasantly enough, and Nijimura has the urge to just cover his face with his hands at that moment. Because there with Atsuko was Himuro Tatsuya, the jackass that he became friends with back in LA. "Muro-chin knows Nijimura-san?" Atsuko asked while munching on some Kompeito. "Yeah we became friends back in LA!" Tatsuya answers cheerfully, and Atsuko nods. On the other hand, Nijimura starts to feel his irritation grow.

"Tatsuya, if you knew you were meeting me today then why didn't you just tell me on the phone that you were dating Murasakibara instead of coming here from Akita?" He asks and Tatsuya has the gall to laugh. "I wanted to surprise you! When Murasakibara told me that her former captain wanted to meet me that was pretty shocking, but not as shocking as knowing that her former captain was actually you! Who would have thought huh?"

Instead of speaking to him, Nijimura turns to Murasakibara instead. "Murasakibara, does it really have to be him?" He asks seriously. "Muro-chin?" She then turns to her boyfriend before turning to face her former captain again. "Yup." She answers and Tatsuya looks quite pleased with her answer. But on his part, Nijimura just groans. "Yes, that's what I was afraid of." Tatsuya merely laughs before telling him that they were in-laws from now on, which caused the former captain to groan again.

Later that day, Nijimura will realize with horror that of all the significant others of his underclassmen he's met, Tatsuya is somehow the most decent and that is already saying a lot.

* * *

 **Akashi**

Mayuzumi Chihiro scanned his surroundings until it fell on a male with light brown hair wearing a grey hoodie. He then slips his way through the throng of people easily in order to get to where the other is. "Haru." He calls out, and the shorter male lets out a small shriek before realizing that it is only his cousin. "Damnit Chihiro!" The one known as Haru grounds out before raising an arm holding a pure white shopping bag that says "AniExpo 20XX" in the center.

"Here, your goods from the West Hall." He said, and Chihiro took it before giving its contents a glance over. "Looks like you managed to get a lot." He commented and Haru scoffed. "Of course, I've been going to anime conventions a lot longer than you. What did you expect?" He asked, rolling his eyes. "Yeah, well thanks for the help this time, Haru." Chihiro thanked, and Haru waved him off, before a sharp look appeared on his eyes. "Don't forget our deal."

"I know. I'll get you the limited edition game you want once it's released." He said and watched as his cousin nodded before stalking off probably to return to the convention hall. As he watched him pass through the rather large doors that led to this years Anime Expo, he couldn't help but feel jealous. He too had wanted to spend the whole day at the expo, but he couldn't because of real world obligations. "Reality sucks." He mutters to himself before making his way to the exit.

The only silver lining for today was the fact that he was able to get the limited Kaguya-tan goods that he came here for in the first place, and then some. He scoured the East hall while Haru took the West Hall for him. He had given Haru both money and strict instructions to get him only things that are in line with his tastes, which he supposes his cousin should be familiar with as they've often discussed about their preference in fiction.

"Glad to see that you made it, Chihiro." A red haired teen known as Akashi Seira tells him, and Chihiro shrugs. "I did say that I'd make it in time." He deadpans. "Yes, you did." She returns smoothly, before turning her attention to his shopping bags. ""I see that you've come with quite a haul." She comments and he grunts. She then looks at the large clock at the center of the plaza they were currently at. "It's a bit early, but we should start heading towards the restaurant." She tells him.

He makes a non-committal noise, but falls into step beside her anyways. Soon enough they reach the outdoor restaurant where they are supposed to have lunch with the former Teiko captain. They are seated by the attendant moments later, and Chihiro finally sets his bags down. They don't have to wait long as Nijimura arrives within ten minutes. They are introduced to each other, and have polite small talk over lunch.

On the inside he was very relieved. His former vice-captain, Akashi had found a good person to be with. Sure Mayuzumi was snarky, and wasn't exactly Mr. Congeniality, but he was a decent person. They had an interesting dynamics to be sure, but he could tell that despite this, their relationship worked. But unfortunately for Nijimura, his good mood was not meant to last. Shortly after they paid the bill, they stood up from their seats with intent to leave.

But in doing so, one of the shopping bags accidentally hit Mayuzumi's legs. Said bag fell forward and its contents spilled. Nijimura, seeing what happened went to help the other gather the anime related merchandise until his eyes landed on a certain doujinshi, which had the title of _Tentacle Princess 4-Can't Get Enough of the Tentacle._ But that incriminating title wasn't even the worst part. No, the worst part was the fact that the scantily clad female character on the cover surrounded by several tentacles, had long red hair, dichromatic eyes and kind of resembled Akashi Seira.

* * *

When Mayuzumi stumbles home after dodging death glares and a pair of red scissors, he thinks to himself that the first thing he's going to do tomorrow was to go to his cousin's house and burn his hidden collection of Yuno-pyon goods. Preferably in front of said cousin. That would teach Haru not to mix up his 3D tastes for his 2D tastes. Not to mention the fact that the character looking like his real life girlfriend was not a good reason to buy him a Tentacle rape doujinshi(that he's not even into).

* * *

 **Kuroko**

By the time he reached Maji burger in order to meet Kuroko's boyfriend, Nijimura decided to keep his expectations at the bare minimum. Previous experience taught him to expect the worst, while hoping for the best. But when he meets Kuroko's beau, he doesn't quite know what to think. The male was well spoken, no doubt about that, but there was something off about him. But it finally hits him later when he slips in several jabs between pleasant conversations on something trivial.

Nijimura can guess by then that behind his pleasant façade is a horrible personality. Truth be told, it wasn't his first time meeting someone like him. Kuroko also seems to be aware of his true nature as well, but she still likes him regardless. So there's that. Also, it looks like the guy is serious about Kuroko, which is a definite plus in his books. As he finishes off the last of his burger, he decides that Imayoshi Shoichi is perfectly fine in-law material.

* * *

 **Thanks for Reading**

A/N- The only "in-laws" that Shuuzo gives his full blessing to are:

Imayoshi Shoichi  
Himuro Tatsuya(barely)

The others as Shuuzo perceives them:

Riko- scary high school girl who hunts innocent little ducks down with a kitchen knife.  
Kagami -a pervert with streaking tendencies.  
Takao- as a pervert who has no qualms displaying his fetishes in broad daylight and while in public.  
Kasamatsu- As someone who regularly hits his own girlfriend out in public. Though considering how Kise doesn't seem to mind, he sees them as a very open S&M couple rather than an aggressor and victim. Mayuzumi-is a male with questionable/if not disturbing fetishes.


End file.
